1. Field of the Invention
The present invention relates to an information recording method and apparatus for recording information into an information recording medium having sectors as recording unit formed thereon such as hard disc, optical disc, etc. under defective-sector management.
2. Description of Related Art
Conventionally, when a hard disc or optical disc having a defective sector, if any, is used in a disc drive, a defective sector management system inside the disc drive replaces the defective sector with a normal one, so that the recording medium will appear as if it had no such defective sector.
A conventional procedure of recording a date into a recording medium will be briefly described with reference to FIG. 1.
Generally, when a data is recorded into a recording medium 101 such as hard disc or optical disc, the data is directed to the recording medium via an OS (operation system). More particularly, the data is forwarded from an application through an OS core 105, file system 104, device driver 103 and a read/write device 102 in this order and then passed to the recording medium 101 as shown in FIG. 1.
In a procedure of reproducing a data from the recording medium 101, the data read from the medium 101 is directed through the read/write device 102, device driver 103, file system 104 and OS core 105 in this order and then passed to an application.
For recording or reproducing a data into or from the recording medium 101, the read/write device 102 will deal with a defective sector, if any, on the recording medium 101, so the stages above the device driver 103 can handle the data as if there were no defect sector on the recording medium 101.
A variety of methods of dealing with a defective sector adopted in the read/write head 102 has been proposed, typically including a slipping method and linear-replacement method.
These conventional methods of dealing with a detective sector will be discussed below with reference to FIG. 2. It is assumed, for example, in FIG. 2(A) the a twelfth physical address is a defective sector and hundredth and subsequent physical addresses are provided as substitute sectors.
The slipping method is such that when a defective sector is found by the medium check during disc initialization, a sector physically next to the defective sector is used as substitute sector.
In this slipping method, the thirteenth and subsequent physical addresses next to the twelfth physical address are used as substitute sectors for the twelfth and subsequent logical addresses as shown in FIG. 2(B).
As mentioned above, since a sector located downstream of a defective sector found is used as a substitute sector in the slipping method, no time of seek for a substitute sector is required with little reduction of data transfer rate of the disc drive. However, since it is necessary to locate and register all detective sectors in a recording medium before actually using the medium, a recording medium going to be used has to be checked for defects or defective sectors beforehand.
On the other hand, the linear-replacement method is such that some locations in a recording medium are provided as substitute sectors in advance during disc initialization and when a defective sector is found, one of the locations is used as substitute sector for the defective sector.
In the linear-replacement method, the hundredth physical address as substitute sector, in place of the twelfth physical address being the defective sector, corresponds to a physical address for a twelfth logical address as shown in FIG. 2(C).
This linear-replacement method is employed for dealing with a defective sector found after the recording medium is put into use. Since substitute sectors are placed separately from the detective sector on the recording medium, an extra time is required for seeking the substitute sector, which will result in a reduced data transfer rate of the disc drive. Thus, when an audio or video signal is being recorded or reproduced with respect to the recording medium, sound or image may possibly appear not continuous.
Digital audio and video information for recording into a recording medium are in various kinds such as audio and video stream data, stream data attributes, record of reproduced order of stream data, information on mapping of divided stream data on a recording medium, information on usable area on a recording medium, etc.
As will be seen from the foregoing, the conventional detective sector dealing methods handle the defective sectors in a stereotyped manner irrespectively of the kind of a data recorded on a recording medium. Therefore, a detector sector in a stream data and a one in an information on a stream mapping are handled in a same manner.
Of the above defective sectors, the defective sector found in the stream mapping information can successfully be dealt with by the linear-placement method. When the defective sector in a stream data is handled by this linear-placement method, however, the data transfer rate is reduced so that audio or video signal cannot successfully be recorded or reproduced.
On the other hand, the slipping method can successfully deal with a defective sector already existent on a recording medium when the medium is used. However, a recording medium has to be checked for any defect on the front side thereof before it is used for recording, which will lead to an increased manufacturing cost. Further, the slipping method cannot accommodate a defective sector found in a recording medium after the medium is used.
From the standpoint of the cost of a recording medium, if the quality of an audio or video information to be recorded into the recording medium is not considered so important, a defective sector found in a mapping management information has to be replaced with a normal sector but a one found in a stream data should not be so replaced as the case may be.
Accordingly, the present invention has an object to overcome the above-mentioned drawbacks of the prior art by providing an information recording method and apparatus adapted to prevent a rate at which a digital audio or video signal for recording into a recording medium is transferred from being reduced depending upon the kind of the signal, and which will not lead to any increase of manufacturing costs for the recording medium.
The above object can be attained by providing an information recording method in which data is recorded into a recording medium taking as recording unit a sector corresponding to a predetermined amount of information signal, comprising, according to the present invention, the steps of:
classifying an information signal for recording into the recording medium into any one of two or more groups depending upon the kind of the information signal; and
recording the information signal into the recording medium while dealing with a defective sector, if any, in a manner designated for the group to which the information signal has been classified to belong at the above classifying step.
The above object can also be attained by providing an information recording apparatus for recording data into a recording medium taking as recording unit a sector corresponding to a predetermined amount of information signal, comprising, according to the present invention:
means for classifying an information signal for recording into the recording medium into any one of two or more groups depending upon the kind of the information signal; and
means for recording the information signal into the recording medium while dealing with a defective sector, if any, in the recording medium in a manner designated for the group to which the information signal has been classified to belong at the above classifying step.
These objects and other objects, features and advantages of the present intention will become more apparent from the following detailed description of the preferred embodiments of the present invention when taken in conjunction with the accompanying drawings.